MS 400 Petrol Chainsaw

Engineered for professional forestry and arboriculture, the MS 400 C-M pairs STIHL’s latest M-Tronic 3.0 auto-tuning system with the industry’s first magnesium piston, boosting displacement to 66.8 cm³ without adding weight and raising output to 4.0 kW—half a kilowatt more than the MS 362 C-M. The result is razor-sharp throttle response and a class-leading power-to-weight of 1.45 kg/kW that crews feel from the first cut. A slim Light 04 guide bar is around 200 g lighter than the Rollomatic E and, with narrow-kerf 3/8″ RS3 chain, slices up to 20% faster while improving balance for less fatigue in the hinge.

Key features

• Magnesium piston technology – first in the world, giving higher RPM headroom without extra weight.
• 66.8 cm³ 2-MIX engine (4.0 kW) – 5.4 bhp with ~20% lower fuel use vs. non-stratified engines.
• M-Tronic 3.0 auto-tuning – adjusts fuel/ignition for altitude, temperature and load; no carb screws.
• Light 04 bar + 3/8″ RS3 chain – 200 g lighter bar and narrower kerf give ~20% faster cut.
• HD2 fleece filter with pre-separation – traps dust to 0.5 µm, extending filter life up to 5×.
• Controlled-delivery oil pump – dial flow to save up to 50% chain-oil on short bars.
• Professional anti-vibration – handles register ~3.5 / 3.5 m/s² (ISO 22867).

Technical highlights

Why professionals choose it

The MS 400 C-M delivers 90-cc class acceleration from a 66.8 cm³ engine, yet weighs less than many 60 cc saws; auto-tuning electronics, a lighter bar-and-chain setup, and long-life filtration mean faster felling, snedding and bucking with fewer fuel stops and less downtime.